COLVERT Posted February 18, 2007 Share Posted February 18, 2007 Now that the firing order is set and all injectors have been cleaned and fitted. The engine is working fine for the first 5 or 7 minutes. In these minutes it is very drivable even on high revs and high speed. Afterwards it begans to miss fire and back fire. This could be heard from the intake air manifold. There is also white smoke from the intake. The ecu water temperature is working. What could this be? Colvert Quote Link to comment Share on other sites More sharing options...
geoffbeaumont Posted February 19, 2007 Share Posted February 19, 2007 Is it always about the same amount of time, or is the trigger temperature related (ie. if you rag it so the temperature rises quicker does the misfire start quicker? Does it always start at about the same point on the temperature gauge?). Are we talking about a completely standard petrol fueled V8 here? LPG conversion? Standard ignition? I'm kind of thinking aloud here hoping it'll spark some ideas from other people, but I'd be looking at ignition trouble first, if only because at least nine tenths of the V8 problems I've ever had have been ignition related. It would be well worth checking the condition of your spark plugs and if you can try another set - if you have to replace them, received wisdom is that RV8s don't like fancy plugs, and the best option is a set of NGK BP6ES. There's certainly nothing wrong with them, they last well, are fairly inexpensive and easy to get hold of. Probably worth checking your ignition timing too, though I'd expect less difference between cold and hot behaviour if that was the problem. Not sure if a failed sensor could cause this? Water temperature isn't the only input to the ECU. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted February 19, 2007 Share Posted February 19, 2007 CTS Sensor (coolant temp sensor) can make for wild misfires, as can the ignition amp, have you any spares you can try. How old / what make are the rotor and cap ? There is somewhere here the diagnostic manual with all the tests many have used in the past, its often a matter of having a few educated stabs at the prob - then working through the manual Theres more than a few V8 "Sperts" here so post up the answers to replies so far Nige Quote Link to comment Share on other sites More sharing options...
COLVERT Posted February 19, 2007 Author Share Posted February 19, 2007 So guys the v8 is totaly standard and running with new spark plugs (NKG) and ht leads, new rotor arm. And also running on unleaded fuel. It takes about 5 minutes to work wrong when i start from cold and drive it hard. it only lasts for 5 to 7 min. I heard that it could be caused from the lambda sensors. Some body also told me that some sort of test could be done by using a resistor to give signal to the ecu. do u know the know how. Colvert Quote Link to comment Share on other sites More sharing options...
imspanners Posted February 19, 2007 Share Posted February 19, 2007 So guys the v8 is totaly standard and running with new spark plugs (NKG) and ht leads, new rotor arm. And also running on unleaded fuel. It takes about 5 minutes to work wrong when i start from cold and drive it hard. it only lasts for 5 to 7 min.I heard that it could be caused from the lambda sensors. Some body also told me that some sort of test could be done by using a resistor to give signal to the ecu. do u know the know how. Colvert It is a possibility the engine is going into closed loop fuelling, then if one of the oxygen (lambda) sensors is faulty, it could be causing a lean misfire. Just a quick easy test, would be to warm it up then when the misfire starts, disconnect each oxygen sensor, individually. If the fault disappears that is most probably the sensor that is faulty. Quote Link to comment Share on other sites More sharing options...
Cil111 Posted February 20, 2007 Share Posted February 20, 2007 anki hawn issibek colvert.... pufff xi dwejjaq fik !!!!!! :D Quote Link to comment Share on other sites More sharing options...
gav- Posted February 20, 2007 Share Posted February 20, 2007 procedures are here for hotwire http://www.landroverclub.net//Club/HTML/Ch...rocedures39.htm Quote Link to comment Share on other sites More sharing options...
Range Rover Blues Posted February 24, 2007 Share Posted February 24, 2007 If it's lucas 14CUX engine management you can change the tune select resistor to tell the ECU there are no lambda sensors at all. Quote Link to comment Share on other sites More sharing options...
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